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CAMBRIDGE INTERNATIONAL EXAMINATIONS
0610 BIOLOGY
0610/22
Paper 2 (Core Theory), maximum raw mark 80
This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of
the examination. It shows the basis on which Examiners were instructed to award marks. It does not
indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
which would have considered the acceptability of alternative answers.
Mark schemes should be read in conjunction with the question paper and the Principal Examiner
Report for Teachers.
Cambridge will not enter into discussions about these mark schemes.
Cambridge is publishing the mark schemes for the October/November 2012 series for most IGCSE,
GCE Advanced Level and Advanced Subsidiary Level components and some Ordinary Level
components.
om
.c
MARK SCHEME for the October/November 2012 series
s
er
International General Certificate of Secondary Education
Page 2
Mark Scheme
IGCSE – October/November 2012
General notes
Do not exceed the section sub-totals or question maxima.
Symbols used in mark scheme and guidance notes.
/
separates alternatives for a marking point
;
separates points for the award of a mark
MP
mark point - used in guidance notes when
referring to numbered marking points
A
accept - as a correct response
R
reject – this is marked with a cross and any
following correct statements do not gain
any marks
I
ignore / irrelevant / inadequate – this
response gains no mark, but any following
correct answers can gain marks.
( )
the word / phrase in brackets is not required
to gain marks but sets the context of the
response for credit.
e.g. (waxy) cuticle. Waxy not needed but if
it was described as a cellulose cuticle then
no mark is awarded.
Mitosis
underlined words – this word only
© Cambridge International Examinations 2012
Syllabus
0610
Paper
22
Page 3
Question
Mark Scheme
IGCSE – October/November 2012
Mark Scheme
Syllabus
0610
Mark
annelids
insects
description
hard, jointed exoskeleton,
three pairs of legs;
I – more than 1 line arriving at a description
long cylindrical body,
segmented, has bristles but
no legs;
molluscs
long cylindrical body, not
segmented, no legs;
myriapods
has soft body, head and
muscular foot,
most have a hard shell;
nematodes
exoskeleton, segmented
body, jointed legs on each
segment;
Any four – 1 mark each
Guidance
If more than 1 line from any group – no mark for this
group
1
group
Paper
22
[4]
[Total: 4]
© Cambridge International Examinations 2012
Page 4
2
(a)
Mark Scheme
IGCSE – October/November 2012
Any two – 1 mark each
[2]
(ii) carbon dioxide;
[1]
(iii) urea and salts;
[1]
R – if any ref to glucose
A – other correctly named substances
Note both for 1 mark
A – renal artery;
B – urethra;
1
2
3
4
5
6
7
8
[2]
A – duodenum or ileum
amino acids absorbed in (small) intestine;
carried to liver;
by hepatic portal vein;
(amino acids) converted to urea;
(urea) carried to the kidney;
in blood (plasma);
(urea) removed from the blood;
(excreted via) bladder / urethra;
A – deamination
R – wrong substances
[4]
Any four – 1 mark each
[Total: 10]
3
(a)
Paper
22
I – refs to examples
A – tissues
(i) 1 removal of waste from body;
2 (waste) formed by body cells / metabolic (waste);
3 ref to substances that are toxic / in excess;
(b)
(c)
Syllabus
0610
(tomato)
(juicy / fleshy part of) fruit eaten by animal;
(seeds) carried away on beak / dropped in faeces;
(dandelion)
very light / ref to parachute / seed buoyant;
blown by wind / floats to ground;
A – bird, mammal
[2]
[2]
© Cambridge International Examinations 2012
Page 5
(b)
1
2
3
4
5
6
Mark Scheme
IGCSE – October/November 2012
Syllabus
0610
large numbers of seeds produced;
to colonise new areas;
need to avoid competition (with parent plant);
need to avoid competition with other seedlings;
for light / water / minerals / space;
increase chance of survival from disease / natural
disasters;
Paper
22
A – form new colonies
Any three – 1 mark each
[3]
[Total: 7]
4
(a)
Nitrogen
[1]
(b)
(i) 0.5 (dm3);
[1]
(ii) 16;
[1]
(iii) 8 (dm3);
[1]
A – ecf from (i) and (ii)
(iv) 8 × 5/100;
[1]
A – ecf from (iii)
0.4 (dm3);
[2]
Correct answer but no working shown 2 marks
© Cambridge International Examinations 2012
Page 6
(c)
Mark Scheme
IGCSE – October/November 2012
Paper
22
[1]
(i) (both) increase;
(ii) 1
2
3
4
5
Syllabus
0610
Ref to more (or equivalent) needed at least once in
responses
Note – response must be in context of breathing, gas
exchange
allows them to take in more air;
can absorb more oxygen;
for more respiration / release more energy;
can remove more carbon dioxide;
ref to more muscle contraction;
[2]
Any two – 1 mark each
(iii) 1
2
3
4
5
6
Note – response must be in context of circulation
heart rate increases (during exercise);
increases rate of blood flow;
blood transports oxygen / glucose;
increase delivery (of oxygen / glucose) to cells / tissue;
increases removal of carbon dioxide / heat / waste from
cells / tissues;
ref to muscle contraction;
[3]
Any three – 1 mark each
[Total: 12]
© Cambridge International Examinations 2012
Page 7
5
(a)
(i) 1
2
3
4
Mark Scheme
IGCSE – October/November 2012
Syllabus
0610
Paper
22
A – ref to autotrophic
A – food web
(only) organisms that can photosynthesise;
incorporate / trap energy into system;
convert light energy into chemical energy;
provide energy / food for all other species / rest of food
chain / web / OWTTE;
[3]
Any three – 1 mark each
(ii) mouse;
katydid;
tapir;
howler monkey;
sloth;
Any two – 1 mark only
[1]
(iii) (trophic level) 3;
[1]
need all five species
A – boa, constrictor, snake
(iv) tree / other plant, katydid, frog, (blue-crowned)
motmot, boa constrictor;
five organisms in correct order (as shown by arrows);
(b)
[2]
starting with producer on left
[2]
A – more food supply
numbers are likely to increase;
less competition for food / sloths / howler monkeys;
(c)
Note – two herbivores for 1 mark
1
2
3
4
5
less food as many species destroyed / become extinct;
less materials (for use);
soil becomes less fertile / eroded;
(thus) less land for growing food crops;
increased risk of flooding / landslips;
Any two – 1 mark each
A – one other valid suggestion
[2]
[Total: 11]
© Cambridge International Examinations 2012
Page 8
6
(a)
Mark Scheme
IGCSE – October/November 2012
(i) S – umbilical cord
T – uterus (wall);
(ii) 1
2
3
4
5
6
[1]
transfer of materials / OWTTE;
by diffusion;
between blood (system) of mother and fetus;
e.g. oxygen / glucose / amino acids (to fetus);
carbon dioxide / urea (from fetus);
progesterone (from placenta) maintains uterine lining /
prevents miscarriage;
3
Paper
22
both correct for 1 mark
A – womb
I – ref to lining
A – embryo, baby
A - waste (from fetus)
[3]
Any three – 1 mark each
(iii) 1
2
Syllabus
0610
mother’s blood at higher pressure than fetal blood;
mother’s blood would burst fetal blood vessels;
4
mother’s blood can be a different blood group to fetal
blood;
this will avoid coagulation of fetal blood;
5
6
mother’s blood can carry pathogens;
fetus not infected;
7
8
mother’s blood can carry toxins / drugs;
fetus not poisoned / affected;
A – can damage organs e.g. brain, kidney, etc
A – blood type
A – avoid blood clotting, A – ‘rejection’ of blood /
OWTTE
A – named example
A – named example
Any two pairs – 2 marks each
[4]
(b)
produces normal haemoglobin;
[1]
(c)
(i) bb;
[1]
(ii) Bb;
[1]
(iii) Bb;
[1]
A – does not have beta thalassaemia
© Cambridge International Examinations 2012
Page 9
(d)
Mark Scheme
IGCSE – October/November 2012
father and mother;
Syllabus
0610
[1]
Paper
22
both for 1 mark
A – the parents
[Total: 13]
7
(a)
(b)
1
2
3
evaporation;
condensation / cooling;
transpiration;
1
2
3
4
passage of water washes away / erodes soil particles;
(leads to) thin / unstable soil on mountain sides
mineral salts dissolve;
leaching;
[3]
A – evapotranspiration or evaporation
I – refs to nutrients
A – (mineral salts) carried away by water flow
[2]
Any two - 1 mark each
[Total: 5]
8
(a)
(i) A – cuticle;
B – palisade (layer / mesophyll);
[2]
I – mesophyll unqualified
(ii) prevent / reduce water loss / evaporation;
[1]
A – excludes pathogens
(iii) to allow diffusion / movement of gases into / out
of the leaf;
[1]
A – refs to oxygen, carbon dioxide, water vapour, open
and close stomata
© Cambridge International Examinations 2012
Page 10
(b)
Mark Scheme
IGCSE – October/November 2012
Syllabus
0610
[1]
(i) 6 pm;
(ii) points correctly plotted; ± half mm square
A – up to 2 plotting errors
[2]
points joined by line;
(iii) from 4:30 pm (± 10) to 4:50 am (± 10);
[1]
(iv) they are open;
[1]
(v) light;
[1]
A – values, in correct sequence, from candidate’s graph
If (b)(v) wrong or blank accept set of responses below:
A – light intensity increases;
A – stomata open more;
A – easier for diffusion to occur
(vi) wind speed increases;
removes saturated air from area of leaf;
increases diffusion gradient / easier for diffusion to occur /
increase rate of diffusion;
OR
rise in temperature;
air can hold more water vapour;
increases rate of diffusion / increases diffusion gradient;
OR
fall in humidity (in atmosphere);
air can hold more water vapour;
increases diffusion gradient / increases rate of diffusion /
easier for diffusion to occur;
Any set of three – 1 mark each
Paper
22
[3]
[Total: 13]
© Cambridge International Examinations 2012
Page 11
9
Mark Scheme
IGCSE – October/November 2012
(a)
girl in GB eats much more than the girl in Africa;
(b)
1
2
3
4
1
2
3
4
[1]
Paper
22
A – correct numerical response based on data in table
as less excess sugars converted to fat;
African girl less likely to be obese;
less acid formed by bacteria (from sweets and sugar);
less likely to suffer from tooth decay;
[2]
Any two – 1 mark each
(c)
Syllabus
0610
cannot form new cytoplasm / cell membranes /
enzymes;
growth slower / less growth (of bones and muscles) / ref
to kwashiorkor;
OR
difficulty in producing some hormones;
onset of puberty / development delayed;
Either response pattern – 2 marks
2 A – refs to maintenance, repair
[2]
[Total: 5]
© Cambridge International Examinations 2012